[Favorable response of advanced hepatocellular carcinoma to proper hepatic arterial administration of cytokines and the significance of the administration].

The objectives in administering anti-cancer therapeutics to the feeding artery of the tumor are to allow the agent to come in direct contact with the tumor cells, to lower the concentration of the agent in body circulation, to lessen the severity of side effects, and to augment efficacy of the agent. A remarkable partial regression was observed in two patients with advanced hepatocellular carcinoma, both at the stage in which surgical excision was diagnosed impossible; one was given successive and daily bolus administration of OH-1, a anti-tumor agent consisting of natural human tumor necrosis factor-alpha (nHuTNF-alpha) and natural human interferon (nHulFN-alpha), and the other a successive and daily combined bolus administration of OH-1 and 5-FU. On investigating the role of the anti-cancer activity of OH-1 by analyzing the NK activity of rat liver large granular lymphocytes, we found that the NK activity was suppressed dose-dependently by nHuTNF-alpha, but not significantly. Thus, an increase in TNF dose in hepatic artery therapy seems undesirable from the standpoint of NK activity. The authors are presently carrying out investigations to elucidate the effector mechanism of the anticancer activity of OH-1.